1. Field of the Invention
The present invention relates generally to food processing machinery, and more specifically to a system for placing food products such as meat patties onto papers suitable for separating patties in a stack.
2. Description of the Prior Art
Automation generally has made large inroads into the food preparation and processing industry. Automating as much as possible of the material handling and packaging of food products decreases costs and improves product consistency.
One part of the industry in which product handling can be automated is in the separation of meat patties and similar products with thin sheets of waxed paper or other material. For example, in packaging a plurality of meat patties in a stack, placing individual sheets of a material such as waxed paper between each patty prevents the meat from sticking together. This is desirable for patties which are frozen as well as those which are simply refrigerated. Preformed meat patties separated by thin sheets of paper are used in large numbers by the fast food hamburger industry.
Many different systems have been designed and built to perform this function. For example, U. S. Pat. No. 3,388,529 describes a machine for shaping meat patties and stacking them with cut sheets of paper between each item. The mechanism for stacking the patties on paper is included as part of the mechanism for forming the patties.
U. S. Pat. Nos. 3,461,483 and 3,675,387 describe systems for placing preformed meat patties onto a square of paper. Both of these patents describe embodiments in which paper is provided on a continuous roll, and cut into squares prior to the patty being placed on them. Since the square can be cut individually from a roll as needed, it is not necessary to provide large stacks of more expensive pre-cut paper.
U. S. Pat. No. 3,783,577 shows a different approach, in which a block having a number of pre-cut square patties is placed onto a sheet of flexible material before it is cut from the roll. The material is a plastic material which can be cut using a hot wire. A controller is used to play out the plastic material at a speed slower than a conveyor carrying the rectangular block of patties and the plastic material so that it remains under tension. When the block of patties reaches a cutting point, the conveyors are stopped and the plastic cut by passing a hot wire through it. The conveyor is then restarted and the block of patties is transported to the next processing station.
There are a number of drawbacks to using the prior art systems described above. Systems which use pre-cut paper sheets require a relatively complex handling mechanism for separating the sheets. In addition, the material cost for the pre-cut paper is relatively high. Several of the references describe systems in which paper squares are cut from a roll immediately prior to use. This has a lower material cost, but the relatively complex mechanism required for cutting and handling the square sheets of paper is fairly expensive and requires a fairly complex maintenance procedure. The '577 patent describes a system in which the meat patties are placed on the material prior to its being cut, which simplifies the system. However, a relatively complex control system is required to start and stop the conveyors for cutting, and to pay out the material off of the supply roll at a rate which is slower than the movement rate of the conveyor belt.
It would be desirable to provide a system for handling food products such as meat patties which is much simpler and less expensive than currently available designs. It would be further desirable for such a system be able to take advantage of the cheaper material costs of uncut paper.